This application is based on and claims priority under 35 U.S.C. xc2xa7 119 with respect to Japanese Application No. 11(1999)-276670 filed on Sep. 29, 1999, the entire content of which is incorporated herein by reference.
The present invention generally relates to vehicle seats. More particularly, the present invention pertains to a vertical seat positioning control device for a vehicle seat assembly.
German Patent Application DE-44 08 219 discloses a seat device for a vehicle seat assembly that includes a stopper mechanism for a vertical positioning device. The vertical positioning device engages a seat side member at its one side and engages an upper rail of the seat slide device at its other end through the stopper mechanism at the uppermost adjusting position. A seat belt is fixed to the seat side member for assuring the optimized restrained position for a seated occupant of the vehicle, regardless of any seat adjusting position in the front and rear directions.
With this known vertical positioning device, when the seat is used at the lowermost vertical position and receives an excessive load exceeding its mechanism load capacity and transmitted from the seat belt device through the seat side member, the seat side member is moved by the load from the lowermost position to the uppermost position and engages the upper stopper. The seat side member is accelerated during this up word movement, and upon the seat side member reaching the upper stopper, the vertical positioning device and the seat side member receive a greatly increased or magnified load. This thus requires a construction that is strong enough to endure this increased or magnified load.
According to the present invention, a seat vertical positioning device for a vehicle seat includes a seat side member supported by the vehicle seat, a bracket fixed to a vehicle floor side member and a link having on end pivotally connected with the bracket at a first pivot point and another end pivotally connected with the seat side member at a second pivot point. The seat vertical positioning device further includes a pin for moving the first pivot point of the link relative to the bracket when the seat side member receives a load which exceeds a predetermined value. A plurality of recesses are formed on the bracket at a position separated from the first pivot point, and a lock pin is fixed to the link and engageable with the recesses when the pivot point of the link is moved.
With this construction, upon application of an excessive load to the vertical positioning device from a seat belt device, the vertical positioning device engages one of the recesses within the height adjusting area for receiving such load. Thus, the vertical positioning device can be structured without having any heavy or large structure for receiving a larger load from the seat belt.
According to another aspect of the invention, a seat vertical positioning device for a vehicle seat includes a seat side member supported by the vehicle seat, a floor side member supported on a vehicle floor, a bracket fixed to the floor side member, and a link pivotally connected to the bracket by a first pin passing through respective first holes in the bracket and the link to permit the link to rotate relative to the bracket. The link is also pivotally connected to the seat side member A lock pin passes through respective second holes in the bracket and the link, with the first hole in the bracket being larger than the first hole in the link and the second hole in the bracket being larger than the second hole in the link so that in addition to rotating relative to the bracket, the link is adapted to shift relative to the bracket when the seat side member receives a load exceeding a predetermined value.
A seat vertical positioning device for a vehicle seat according to another aspect of the invention includes a seat side member for supporting the vehicle seat, a floor side member adapted to be supported on a vehicle floor, a bracket fixed to the floor side member, a link pivotally connected to the bracket by a first pin passing through a hole in the link and an elongated hole in the bracket to permit the link to rotate relative to the bracket about a pivot point during vertical adjustment of the vehicle seat while also permitting the link to shift relative to the bracket to move the pivot point when the seat side member receives a load exceeding a predetermined value. The link is also pivotally connected to the seat side member by a second pin. A lock pin is fixed to the link and movable with respect to the bracket to engage a portion of the bracket when the seat side member receives a load exceeding a predetermined value.